Re: console spin_lock

[Russell King <rmk@arm.linux.org.uk>]

Andrew Morton writes:
> The subtler problem will be interrupt-capable drivers which
> do a bare spin_lock() to serialise wrt their interrupt routines,
> relying upon interrupts being disabled.  They'll be deadlocky
> and will need changing.  That's trivial to find and fix though.

Uhh, what if you have this situation:

interrupt (level triggered)
 enter interrupt handler
   printk (can re-enable interrupts?)
     enter interrupt handler
       printk (can re-enable interrupts?)
         enter interrupt handler
           printk (can re-enable interrupts?)
             ....

So surely this isn't a new problem?
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